Mapping between a control beam and a data channel beam

ABSTRACT

There is a need for a beam tracking technique that reduces the time needed to perform a beamforming procedure and that reduces beam overhead. The apparatus may determine a mapping between a first beam associated with a first type of channel and a second beam associated with a second type of channel. In an aspect, the first type of channel may be different than the second type of channel. The apparatus may receive the first beam associated with the first type of channel and the second beam associated with the second type of channel. In an aspect, the first beam and the second beam may be received from a second device.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application Ser.No. 62/379,208, entitled “MAPPING BETWEEN CONTROL AND DATA BEAMS” andfiled on Aug. 24, 2016, which is expressly incorporated by referenceherein in its entirety.

BACKGROUND Field

The present disclosure relates generally to communication systems, andmore particularly, to a mapping between a control channel beam and adata channel beam.

Background

Wireless communication systems are widely deployed to provide varioustelecommunication services such as telephony, video, data, messaging,and broadcasts. Typical wireless communication systems may employmultiple-access technologies capable of supporting communication withmultiple users by sharing available system resources. Examples of suchmultiple-access technologies include code division multiple access(CDMA) systems, time division multiple access (TDMA) systems, frequencydivision multiple access (FDMA) systems, orthogonal frequency divisionmultiple access (OFDMA) systems, single-carrier frequency divisionmultiple access (SC-FDMA) systems, and time division synchronous codedivision multiple access (TD-SCDMA) systems.

These multiple access technologies have been adopted in varioustelecommunication standards to provide a common protocol that enablesdifferent wireless devices to communicate on a municipal, national,regional, and even global level. An example telecommunication standardis Long Term Evolution (LTE). LTE is a set of enhancements to theUniversal Mobile Telecommunications System (UMTS) mobile standardpromulgated by Third Generation Partnership Project (3GPP). LTE isdesigned to support mobile broadband access through improved spectralefficiency, lowered costs, and improved services using OFDMA on thedownlink, SC-FDMA on the uplink, and multiple-input multiple-output(MIMO) antenna technology. However, as the demand for mobile broadbandaccess continues to increase, there exists a need for furtherimprovements in LTE technology. These improvements may also beapplicable to other multi-access technologies and the telecommunicationstandards that employ these technologies.

One way to meet the increasing demand for mobile broadband may be toutilize the millimeter wave (mmW) spectrum in addition to LTE. However,communications using the mmW radio frequency band have extremely highpath loss and a short range. Beamforming may be used to compensate forthe extreme high path loss and short range. Beamforming techniques andmethods are currently needed for providing seamless and continuouscoverage for a UE operating in the mmW radio frequency band.

SUMMARY

The following presents a simplified summary of one or more aspects inorder to provide a basic understanding of such aspects. This summary isnot an extensive overview of all contemplated aspects, and is intendedto neither identify key or critical elements of all aspects nordelineate the scope of any or all aspects. Its sole purpose is topresent some concepts of one or more aspects in a simplified form as aprelude to the more detailed description that is presented later.

One way to meet the increasing demand for mobile broadband may be toutilize the mmW spectrum in addition to LTE. Communications using themmW radio frequency band have extremely high path loss and a shortrange. Beamforming may be used to compensate for the extreme high pathloss and short range. However, due to the potentially large number ofantennas at an mmW base station and subarrays at a user equipment (UE),the number of possible beams that may need to be scanned during abeamforming procedure can be quite large especially when a controlchannel and an associated data channel are transmitted using differentbeams. A scanning process for a large number of potential beams may takean undesirable amount of time and create significant beam overhead.There is a need for a beam tracking technique that reduces the timeneeded to perform a beamforming procedure and that reduces beamoverhead.

The present disclosure provides a solution to the problem by providing arelationship between the beam used for a control channel and a beam usedfor the associated data channel. In a first aspect, the beam used forthe control channel and the beam used for the associated data channelmay be correlated via an explicit mapping or an implicit mapping of thedifferent beams. In a second aspect, the relationship between the beamused for the control channel and the beam used for the associated datachannel may be independent, without an explicit or implicit mapping. Inthe second aspect, the beams may be selected without any correlationtherebetween based on signaling that indicates which beam will be usedfor the control channel and which beam will be used for the datachannel. In this way, the present disclosure may speed up thebeamforming procedure and reduce beam overhead by decreasing the numberof potential beams that may need to be scanned.

In an aspect of the disclosure, a method, a computer-readable medium,and an apparatus are provided. The apparatus may determine a mappingbetween a first beam associated with a first type of channel and asecond beam associated with a second type of channel. In an aspect, thefirst type of channel may be different than the second type of channel.The apparatus may receive the first beam associated with the first typeof channel and the second beam associated with the second type ofchannel. In an aspect, the first beam and the second beam may bereceived from a second device.

To the accomplishment of the foregoing and related ends, the one or moreaspects comprise the features hereinafter fully described andparticularly pointed out in the claims. The following description andthe annexed drawings set forth in detail certain illustrative featuresof the one or more aspects. These features are indicative, however, ofbut a few of the various ways in which the principles of various aspectsmay be employed, and this description is intended to include all suchaspects and their equivalents.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating an example of a wireless communicationssystem and an access network.

FIGS. 2A, 2B, 2C, and 2D are diagrams illustrating LTE examples of a DLframe structure, DL channels within the DL frame structure, an UL framestructure, and UL channels within the UL frame structure, respectively.

FIG. 3 is a diagram illustrating an example of an evolved Node B (eNB)and user equipment (UE) in an access network.

FIG. 4A is a diagram of an mmW communication system that may enable asynchronization and beam tracking procedure in accordance with certainaspects of the disclosure.

FIG. 4B is a diagram of a first group of beams that may be used inaccordance with certain aspects of the disclosure.

FIG. 4C is a diagram of a second group of beams that may be used inaccordance with certain aspects of the disclosure.

FIG. 4D is a diagram of a first set of fine beams that may be used inaccordance with certain aspects of the disclosure.

FIG. 4E is a diagram of a second set of fine beams that may be used inaccordance with certain aspects of the disclosure.

FIG. 4F is a diagram of an mmW communication system that may provide arelationship between a control channel beam and a data channel beam inaccordance with certain aspects of the disclosure.

FIGS. 5A-5C are a flowchart of a method of wireless communication.

FIG. 6 is a conceptual data flow diagram illustrating the data flowbetween different means/components in an example apparatus.

FIG. 7 is a diagram illustrating an example of a hardware implementationfor an apparatus employing a processing system.

DETAILED DESCRIPTION

The detailed description set forth below in connection with the appendeddrawings is intended as a description of various configurations and isnot intended to represent the only configurations in which the conceptsdescribed herein may be practiced. The detailed description includesspecific details for the purpose of providing a thorough understandingof various concepts. However, it will be apparent to those skilled inthe art that these concepts may be practiced without these specificdetails. In some instances, well known structures and components areshown in block diagram form in order to avoid obscuring such concepts.

Several aspects of telecommunication systems will now be presented withreference to various apparatus and methods. These apparatus and methodswill be described in the following detailed description and illustratedin the accompanying drawings by various blocks, components, circuits,processes, algorithms, etc. (collectively referred to as “elements”).These elements may be implemented using electronic hardware, computersoftware, or any combination thereof. Whether such elements areimplemented as hardware or software depends upon the particularapplication and design constraints imposed on the overall system.

By way of example, an element, or any portion of an element, or anycombination of elements may be implemented as a “processing system” thatincludes one or more processors. Examples of processors includemicroprocessors, microcontrollers, graphics processing units (GPUs),central processing units (CPUs), application processors, digital signalprocessors (DSPs), reduced instruction set computing (RISC) processors,systems on a chip (SoC), baseband processors, field programmable gatearrays (FPGAs), programmable logic devices (PLDs), state machines, gatedlogic, discrete hardware circuits, and other suitable hardwareconfigured to perform the various functionality described throughoutthis disclosure. One or more processors in the processing system mayexecute software. Software shall be construed broadly to meaninstructions, instruction sets, code, code segments, program code,programs, subprograms, software components, applications, softwareapplications, software packages, routines, subroutines, objects,executables, threads of execution, procedures, functions, etc., whetherreferred to as software, firmware, middleware, microcode, hardwaredescription language, or otherwise.

Accordingly, in one or more example embodiments, the functions describedmay be implemented in hardware, software, or any combination thereof. Ifimplemented in software, the functions may be stored on or encoded asone or more instructions or code on a computer-readable medium.Computer-readable media includes computer storage media. Storage mediamay be any available media that can be accessed by a computer. By way ofexample, and not limitation, such computer-readable media can comprise arandom-access memory (RAM), a read-only memory (ROM), an electricallyerasable programmable ROM (EEPROM), optical disk storage, magnetic diskstorage, other magnetic storage devices, combinations of theaforementioned types of computer-readable media, or any other mediumthat can be used to store computer executable code in the form ofinstructions or data structures that can be accessed by a computer.

FIG. 1 is a diagram illustrating an example of a wireless communicationssystem and an access network 100. The wireless communications system(also referred to as a wireless wide area network (WWAN)) includes basestations 102, UEs 104, and an Evolved Packet Core (EPC) 160. The basestations 102 may include macro cells (high power cellular base station)and/or small cells (low power cellular base station). The macro cellsinclude eNBs. The small cells include femtocells, picocells, andmicrocells.

The base stations 102 (collectively referred to as Evolved UniversalMobile Telecommunications System (UMTS) Terrestrial Radio Access Network(E-UTRAN)) interface with the EPC 160 through backhaul links 132 (e.g.,S1 interface). In addition to other functions, the base stations 102 mayperform one or more of the following functions: transfer of user data,radio channel ciphering and deciphering, integrity protection, headercompression, mobility control functions (e.g., handover, dualconnectivity), inter-cell interference coordination, connection setupand release, load balancing, distribution for non-access stratum (NAS)messages, NAS node selection, synchronization, radio access network(RAN) sharing, multimedia broadcast multicast service (MBMS), subscriberand equipment trace, RAN information management (RIM), paging,positioning, and delivery of warning messages. The base stations 102 maycommunicate directly or indirectly (e.g., through the EPC 160) with eachother over backhaul links 134 (e.g., X2 interface). The backhaul links134 may be wired or wireless.

The base stations 102 may wirelessly communicate with the UEs 104. Eachof the base stations 102 may provide communication coverage for arespective geographic coverage area 110. There may be overlappinggeographic coverage areas 110. For example, the small cell 102′ may havea coverage area 110′ that overlaps the coverage area 110 of one or moremacro base stations 102. A network that includes both small cell andmacro cells may be known as a heterogeneous network. A heterogeneousnetwork may also include Home Evolved Node Bs (eNBs) (HeNBs), which mayprovide service to a restricted group known as a closed subscriber group(CSG). The communication links 120 between the base stations 102 and theUEs 104 may include uplink (UL) (also referred to as reverse link)transmissions from a UE 104 to a base station 102 and/or downlink (DL)(also referred to as forward link) transmissions from a base station 102to a UE 104. The communication links 120 may use MIMO antennatechnology, including spatial multiplexing, beamforming, and/or transmitdiversity. The communication links may be through one or more carriers.The base stations 102/UEs 104 may use spectrum up to Y MHz (e.g., 5, 10,15, 20 MHz) bandwidth per carrier allocated in a carrier aggregation ofup to a total of Yx MHz (x component carriers) used for transmission ineach direction. The carriers may or may not be adjacent to each other.Allocation of carriers may be asymmetric with respect to DL and UL(e.g., more or less carriers may be allocated for DL than for UL). Thecomponent carriers may include a primary component carrier and one ormore secondary component carriers. A primary component carrier may bereferred to as a primary cell (PCell) and a secondary component carriermay be referred to as a secondary cell (SCell).

The wireless communications system may further include a Wi-Fi accesspoint (AP) 150 in communication with Wi-Fi stations (STAs) 152 viacommunication links 154 in a 5 GHz unlicensed frequency spectrum. Whencommunicating in an unlicensed frequency spectrum, the STAs 152/AP 150may perform a clear channel assessment (CCA) prior to communicating inorder to determine whether the channel is available.

The small cell 102′ may operate in a licensed and/or an unlicensedfrequency spectrum. When operating in an unlicensed frequency spectrum,the small cell 102′ may employ LTE and use the same 5 GHz unlicensedfrequency spectrum as used by the Wi-Fi AP 150. The small cell 102′,employing LTE in an unlicensed frequency spectrum, may boost coverage toand/or increase capacity of the access network. LTE in an unlicensedspectrum may be referred to as LTE-unlicensed (LTE-U), licensed assistedaccess (LAA), or MuLTEfire.

The millimeter wave (mmW) base station 180 may operate in mmWfrequencies and/or near mmW frequencies in communication with the UE182. Extremely high frequency (EHF) is part of the RF in theelectromagnetic spectrum. EHF has a range of 30 GHz to 300 GHz and awavelength between 1 millimeter and 10 millimeters. Radio waves in theband may be referred to as a millimeter wave. Near mmW may extend downto a frequency of 3 GHz with a wavelength of 100 millimeters. The superhigh frequency (SHF) band extends between 3 GHz and 30 GHz, alsoreferred to as centimeter wave. Communications using the mmW/near mmWradio frequency band has extremely high path loss and a short range. ThemmW base station 180 may utilize beamforming 184 with the UE 182 tocompensate for the extremely high path loss and short range.

The EPC 160 may include a Mobility Management Entity (MME) 162, otherMMEs 164, a Serving Gateway 166, a Multimedia Broadcast MulticastService (MBMS) Gateway 168, a Broadcast Multicast Service Center (BM-SC)170, and a Packet Data Network (PDN) Gateway 172. The MME 162 may be incommunication with a Home Subscriber Server (HSS) 174. The MME 162 isthe control node that processes the signaling between the UEs 104 andthe EPC 160. Generally, the MME 162 provides bearer and connectionmanagement. All user Internet protocol (IP) packets are transferredthrough the Serving Gateway 166, which itself is connected to the PDNGateway 172. The PDN Gateway 172 provides UE IP address allocation aswell as other functions. The PDN Gateway 172 and the BM-SC 170 areconnected to the IP Services 176. The IP Services 176 may include theInternet, an intranet, an IP Multimedia Subsystem (IMS), a PS StreamingService (PSS), and/or other IP services. The BM-SC 170 may providefunctions for MBMS user service provisioning and delivery. The BM-SC 170may serve as an entry point for content provider MBMS transmission, maybe used to authorize and initiate MBMS Bearer Services within a publicland mobile network (PLMN), and may be used to schedule MBMStransmissions. The MBMS Gateway 168 may be used to distribute MBMStraffic to the base stations 102 belonging to a Multicast BroadcastSingle Frequency Network (MBSFN) area broadcasting a particular service,and may be responsible for session management (start/stop) and forcollecting eMBMS related charging information.

The base station may also be referred to as a Node B, evolved Node B(eNB), an access point, a base transceiver station, a radio basestation, a radio transceiver, a transceiver function, a basic serviceset (BSS), an extended service set (ESS), or some other suitableterminology. The base station 102 provides an access point to the EPC160 for a UE 104. Examples of UEs 104 include a cellular phone, a smartphone, a session initiation protocol (SIP) phone, a laptop, a personaldigital assistant (PDA), a satellite radio, a global positioning system,a multimedia device, a video device, a digital audio player (e.g., MP3player), a camera, a game console, a tablet, a smart device, a wearabledevice, or any other similar functioning device. The UE 104 may also bereferred to as a station, a mobile station, a subscriber station, amobile unit, a subscriber unit, a wireless unit, a remote unit, a mobiledevice, a wireless device, a wireless communications device, a remotedevice, a mobile subscriber station, an access terminal, a mobileterminal, a wireless terminal, a remote terminal, a handset, a useragent, a mobile client, a client, or some other suitable terminology.

Referring again to FIG. 1, in certain aspects, the UE 104 and mmW basestation 180 may be configured to determine a mapping between a beam usedfor a control channel and a different beam used for an associated datachannel (198).

FIG. 2A is a diagram 200 illustrating an example of a DL frame structurein LTE. FIG. 2B is a diagram 230 illustrating an example of channelswithin the DL frame structure in LTE. FIG. 2C is a diagram 250illustrating an example of an UL frame structure in LTE. FIG. 2D is adiagram 280 illustrating an example of channels within the UL framestructure in LTE. Other wireless communication technologies may have adifferent frame structure and/or different channels. In LTE, a frame (10ms) may be divided into 10 equally sized subframes. Each subframe mayinclude two consecutive time slots. A resource grid may be used torepresent the two time slots, each time slot including one or more timeconcurrent resource blocks (RBs) (also referred to as physical RBs(PRBs)). The resource grid is divided into multiple resource elements(REs). In LTE, for a normal cyclic prefix, an RB contains 12 consecutivesubcarriers in the frequency domain and 7 consecutive symbols (for DL,OFDM symbols; for UL, SC-FDMA symbols) in the time domain, for a totalof 84 REs. For an extended cyclic prefix, an RB contains 12 consecutivesubcarriers in the frequency domain and 6 consecutive symbols in thetime domain, for a total of 72 REs. The number of bits carried by eachRE depends on the modulation scheme.

As illustrated in FIG. 2A, some of the REs carry DL reference (pilot)signals (DL-RS) for channel estimation at the UE. The DL-RS may includecell-specific reference signals (CRS) (also sometimes called common RS),UE-specific reference signals (UE-RS), and channel state informationreference signals (CSI-RS). FIG. 2A illustrates CRS for antenna ports 0,1, 2, and 3 (indicated as R₀, R₁, R₂, and R₃, respectively), UE-RS forantenna port 5 (indicated as R₅), and CSI-RS for antenna port 15(indicated as R). FIG. 2B illustrates an example of various channelswithin a DL subframe of a frame. The physical control format indicatorchannel (PCFICH) is within symbol 0 of slot 0, and carries a controlformat indicator (CFI) that indicates whether the physical downlinkcontrol channel (PDCCH) occupies 1, 2, or 3 symbols (FIG. 2B illustratesa PDCCH that occupies 3 symbols). The PDCCH carries downlink controlinformation (DCI) within one or more control channel elements (CCEs),each CCE including nine RE groups (REGs), each REG including fourconsecutive REs in an OFDM symbol. A UE may be configured with aUE-specific enhanced PDCCH (ePDCCH) that also carries DCI. The ePDCCHmay have 2, 4, or 8 RB pairs (FIG. 2B shows two RB pairs, each subsetincluding one RB pair). The physical hybrid automatic repeat request(ARQ) (HARQ) indicator channel (PHICH) is also within symbol 0 of slot 0and carries the HARQ indicator (HI) that indicates HARQ acknowledgement(ACK)/negative ACK (NACK) feedback based on the physical uplink sharedchannel (PUSCH). The primary synchronization channel (PSCH) is withinsymbol 6 of slot 0 within subframes 0 and 5 of a frame, and carries aprimary synchronization signal (PSS) that is used by a UE to determinesubframe timing and a physical layer identity. The secondarysynchronization channel (SSCH) is within symbol 5 of slot 0 withinsubframes 0 and 5 of a frame, and carries a secondary synchronizationsignal (SSS) that is used by a UE to determine a physical layer cellidentity group number. Based on the physical layer identity and thephysical layer cell identity group number, the UE can determine aphysical cell identifier (PCI). Based on the PCI, the UE can determinethe locations of the aforementioned DL-RS. The physical broadcastchannel (PBCH) is within symbols 0, 1, 2, 3 of slot 1 of subframe 0 of aframe, and carries a master information block (MIB). The MIB provides anumber of RBs in the DL system bandwidth, a PHICH configuration, and asystem frame number (SFN). The physical downlink shared channel (PDSCH)carries user data, broadcast system information not transmitted throughthe PBCH such as system information blocks (SIBs), and paging messages.

As illustrated in FIG. 2C, some of the REs carry demodulation referencesignals (DM-RS) for channel estimation at the eNB. The UE mayadditionally transmit sounding reference signals (SRS) in the lastsymbol of a subframe. The SRS may have a comb structure, and a UE maytransmit SRS on one of the combs. The SRS may be used by an eNB forchannel quality estimation to enable frequency-dependent scheduling onthe UL. FIG. 2D illustrates an example of various channels within an ULsubframe of a frame. A physical random access channel (PRACH) may bewithin one or more subframes within a frame based on the PRACHconfiguration. The PRACH may include six consecutive RB pairs within asubframe. The PRACH allows the UE to perform initial system access andachieve UL synchronization. A physical uplink control channel (PUCCH)may be located on edges of the UL system bandwidth. The PUCCH carriesuplink control information (UCI), such as scheduling requests, a channelquality indicator (CQI), a precoding matrix indicator (PMI), a rankindicator (RI), and HARQ ACK/NACK feedback. The PUSCH carries data, andmay additionally be used to carry a buffer status report (BSR), a powerheadroom report (PHR), and/or UCI.

FIG. 3 is a block diagram of an eNB 310 in communication with a UE 350in an access network. In the DL, IP packets from the EPC 160 may beprovided to a controller/processor 375. The controller/processor 375implements layer 3 and layer 2 functionality. Layer 3 includes a radioresource control (RRC) layer, and layer 2 includes a packet dataconvergence protocol (PDCP) layer, a radio link control (RLC) layer, anda medium access control (MAC) layer. The controller/processor 375provides RRC layer functionality associated with broadcasting of systeminformation (e.g., MIB, SIBs), RRC connection control (e.g., RRCconnection paging, RRC connection establishment, RRC connectionmodification, and RRC connection release), inter radio access technology(RAT) mobility, and measurement configuration for UE measurementreporting; PDCP layer functionality associated with headercompression/decompression, security (ciphering, deciphering, integrityprotection, integrity verification), and handover support functions; RLClayer functionality associated with the transfer of upper layer packetdata units (PDUs), error correction through ARQ, concatenation,segmentation, and reassembly of RLC service data units (SDUs),re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; andMAC layer functionality associated with mapping between logical channelsand transport channels, multiplexing of MAC SDUs onto transport blocks(TBs), demultiplexing of MAC SDUs from TBs, scheduling informationreporting, error correction through HARQ, priority handling, and logicalchannel prioritization.

The transmit (TX) processor 316 and the receive (RX) processor 370implement layer 1 functionality associated with various signalprocessing functions. Layer 1, which includes a physical (PHY) layer,may include error detection on the transport channels, forward errorcorrection (FEC) coding/decoding of the transport channels,interleaving, rate matching, mapping onto physical channels,modulation/demodulation of physical channels, and MIMO antennaprocessing. The TX processor 316 handles mapping to signalconstellations based on various modulation schemes (e.g., binaryphase-shift keying (BPSK), quadrature phase-shift keying (QPSK),M-phase-shift keying (M-PSK), M-quadrature amplitude modulation(M-QAM)). The coded and modulated symbols may then be split intoparallel streams. Each stream may then be mapped to an OFDM subcarrier,multiplexed with a reference signal (e.g., pilot) in the time and/orfrequency domain, and then combined together using an Inverse FastFourier Transform (IFFT) to produce a physical channel carrying a timedomain OFDM symbol stream. The OFDM stream is spatially precoded toproduce multiple spatial streams. Channel estimates from a channelestimator 374 may be used to determine the coding and modulation scheme,as well as for spatial processing. The channel estimate may be derivedfrom a reference signal and/or channel condition feedback transmitted bythe UE 350. Each spatial stream may then be provided to a differentantenna 320 via a separate transmitter 318TX. Each transmitter 318TX maymodulate an RF carrier with a respective spatial stream fortransmission.

At the UE 350, each receiver 354RX receives a signal through itsrespective antenna 352. Each receiver 354RX recovers informationmodulated onto an RF carrier and provides the information to the receive(RX) processor 356. The TX processor 368 and the RX processor 356implement layer 1 functionality associated with various signalprocessing functions. The RX processor 356 may perform spatialprocessing on the information to recover any spatial streams destinedfor the UE 350. If multiple spatial streams are destined for the UE 350,they may be combined by the RX processor 356 into a single OFDM symbolstream. The RX processor 356 then converts the OFDM symbol stream fromthe time-domain to the frequency domain using a Fast Fourier Transform(FFT). The frequency domain signal comprises a separate OFDM symbolstream for each subcarrier of the OFDM signal. The symbols on eachsubcarrier, and the reference signal, are recovered and demodulated bydetermining the most likely signal constellation points transmitted bythe eNB 310. These soft decisions may be based on channel estimatescomputed by the channel estimator 358. The soft decisions are thendecoded and deinterleaved to recover the data and control signals thatwere originally transmitted by the eNB 310 on the physical channel. Thedata and control signals are then provided to the controller/processor359, which implements layer 3 and layer 2 functionality.

The controller/processor 359 can be associated with a memory 360 thatstores program codes and data. The memory 360 may be referred to as acomputer-readable medium. In the UL, the controller/processor 359provides demultiplexing between transport and logical channels, packetreassembly, deciphering, header decompression, and control signalprocessing to recover IP packets from the EPC 160. Thecontroller/processor 359 is also responsible for error detection usingan ACK and/or NACK protocol to support HARQ operations.

Similar to the functionality described in connection with the DLtransmission by the eNB 310, the controller/processor 359 provides RRClayer functionality associated with system information (e.g., MIB, SIBs)acquisition, RRC connections, and measurement reporting; PDCP layerfunctionality associated with header compression/decompression, andsecurity (ciphering, deciphering, integrity protection, integrityverification); RLC layer functionality associated with the transfer ofupper layer PDUs, error correction through ARQ, concatenation,segmentation, and reassembly of RLC SDUs, re-segmentation of RLC dataPDUs, and reordering of RLC data PDUs; and MAC layer functionalityassociated with mapping between logical channels and transport channels,multiplexing of MAC SDUs onto TBs, demultiplexing of MAC SDUs from TBs,scheduling information reporting, error correction through HARQ,priority handling, and logical channel prioritization.

Channel estimates derived by a channel estimator 358 from a referencesignal or feedback transmitted by the eNB 310 may be used by the TXprocessor 368 to select the appropriate coding and modulation schemes,and to facilitate spatial processing. The spatial streams generated bythe TX processor 368 may be provided to different antenna 352 viaseparate transmitters 354TX. Each transmitter 354TX may modulate an RFcarrier with a respective spatial stream for transmission.

The UL transmission is processed at the eNB 310 in a manner similar tothat described in connection with the receiver function at the UE 350.Each receiver 318RX receives a signal through its respective antenna320. Each receiver 318RX recovers information modulated onto an RFcarrier and provides the information to a RX processor 370.

The controller/processor 375 can be associated with a memory 376 thatstores program codes and data. The memory 376 may be referred to as acomputer-readable medium. In the UL, the controller/processor 375provides demultiplexing between transport and logical channels, packetreassembly, deciphering, header decompression, control signal processingto recover IP packets from the UE 350. IP packets from thecontroller/processor 375 may be provided to the EPC 160. Thecontroller/processor 375 is also responsible for error detection usingan ACK and/or NACK protocol to support HARQ operations.

One way to meet the increasing demand for mobile broadband may be toutilize the mmW spectrum in addition to LTE. An mmW communication systemmay operate at very high frequency bands (e.g., 10.0 GHz to 300.0 GHz)where the carrier wavelength is on the order of a few millimeters. AnmmW system may operate with the help of a number of antennas andbeamforming to overcome a channel having low gain. For example, heavyattenuation at high carrier frequency bands may limit the range of atransmitted signal to a few tens of meters (e.g., 1 to 50 meters). Also,the presence of obstacles (e.g., walls, furniture, people, etc.) mayblock the propagation of high frequency millimeter waves. As such,propagation characteristics of high carrier frequencies necessitate theneed for directional beamforming between the mmW base station and the UEthat focuses the transmit energy in specific spatial directionscorresponding to the dominant spatial scatterers, reflectors, and/ordiffraction paths to overcome the loss. Beamforming may be implementedvia an array of antennas (e.g., phased arrays) cooperating to beamform ahigh frequency signal in a particular direction to receiving devices,and therefore, extend the range of the signal.

During beamforming, a UE may estimate channel characteristics associatedwith one or more potential access beams and transmit informationassociated with the estimated channel characteristics to an mmW basestation. For example, the channel characteristics of at least one beamreference signal (BRS) and/or at least one beam refinement referencesignal (BRRS) associated with each of the potential access beams may beestimated by the UE. Using the information associated with the estimatedchannel characteristics for each of the potential access beams, the mmWbase station may select an access beam with the most desirable channelcharacteristics and adjust a phase shift of each of the antennas portsused for transmitting the channel such that the channel is spatiallyfocused in the direction of the first device. A spatially focusedchannel may have a better SNR (e.g., level of a desired signal comparedto the level of background noise) than a channel that is not spatiallyfocused. Transmitting a channel with a better SNR (e.g., as compared toa channel with a worse SNR) may increase the data rate that may bereceived at the first device.

FIG. 4A is a diagram illustrating an example of an mmW communicationsystem 400 that may perform beamforming. The mmW communication system400 includes UE 431 and mmW base station 432. In an aspect, the UE 431and mmW base station 432 may perform initial synchronization anddiscovery to establish an access link that may be used for mmWcommunications. For example, the UE 431 and the mmW base station 432 mayestablish an access link along path 417. During initial synchronization,mmW base station 432 may transmit a signal (e.g., a beam referencesignal (BRS)) in a first set of beams (e.g., beams 401, 403, 405, 407)during a first symbol of a synchronization subframe and transmit thesame signal in a second set of beams (e.g., beams 409, 411, 413, 415)during a second symbol of the synchronization subframe that is receivedat UE 431.

In a first aspect, the first set of beams may include beams 401, 403,405, 407 and the second set of beams 409, 411, 413, 415. In one aspect,the first set of beams may be non-adjacent beams selected from a firstgroup of beams as discussed infra with respect to FIG. 4B. In anotheraspect, the second set of beams may be non-adjacent beams selected froma second group of beams as discussed infra with respect to FIG. 4C. Byselecting non-adjacent beams, the mmW base station 432 may sweep through“coarse” beam directions to estimate an L number of directions (alsoreferred to as beamforming directions or angles) corresponding to L beampaths without having to sweep through all of the potential beams duringsynchronization.

FIG. 4B illustrates a first group of fine beams 425 that are separatedby angles smaller than θ. The group of beams 425 illustrated in FIG. 4Bcontain eight different beams that are spatially focused in differentdirections. For example, the group of beams 425 includes beam₁ 401 thatis spatially focused in a first direction, beam₂ 402 that is spatiallyfocused in a second direction, beam₃ 403 that is spatially focused in athird direction, beam₄ 404 that is spatially focused in a fourthdirection, beam₅ 405 that is spatially focused in a fifth direct, beam₆406 that is spatially focused in a sixth direction, beam₇ 407 that isspatially focused in a seventh direction, and beam₈ 408 that isspatially focused in an eighth direction. The number of beamsillustrated in FIG. 4B is meant to be illustrative, and one of ordinaryskill understands that more or fewer beams may be included in the firstgroup of beams without departing from the scope of the presentdisclosure.

FIG. 4C illustrates a second group of fine beams 435 that are separatedby angles smaller than 0. The group of beams 435 illustrated in FIG. 4Ccontain eight different beams that are spatially focused in differentdirections. For example, the group of beams 435 includes beam₉ 409 thatis spatially focused in a ninth direction, beam₁₀ 410 that is spatiallyfocused in a tenth direction, beam₁₁ 411 that is spatially focused in aneleventh direction, beam₁₂ 412 that is spatially focused in a twelfthdirection, beam₁₃ 413 that is spatially focused in a thirteenth direct,beam₁₄ 414 that is spatially focused in a fourteenth direction, beam₁₅415 that is spatially focused in a fifteenth direction, and beam₁₆ 416that is spatially focused in a sixteenth direction. The number of beamsillustrated in FIG. 4C is meant to be illustrative, and one of ordinaryskill understands that more or fewer beams may be included in the secondgroup of beams without departing from the scope of the presentdisclosure.

Referring again to FIG. 4A, UE 431 may determine a strongest beam (e.g.,beam_(n)) in the first set of beams and a strongest beam (e.g.,beam_(v)) in the second set of beams. For example, beam, may be beam₅405 and beam, may be beam₁₃ 413. In the particular example illustratedin FIG. 4A, n=5 and v=13. However, the values n and v are not limited tothose illustrated in FIG. 4A.

After performing the initial synchronization and discovery using thefirst set of beams and the second set of beams, the UE 431 and the mmWbase station 432 may each have an estimate of an L number of directions(also referred to as beamforming directions or angles) corresponding toL beam paths (e.g., 401, 403, 405, 407, 409, 411, 413, 415) from the mmWbase station 432 to the UE 431. In an aspect, L may be an integergreater than 1 (for diversity reasons). In an aspect, the mmW basestation 432 and/or the UE 431 may have an estimate of the relativestrength of these L beam paths allowing initial beamforming to beperformed on the beam path(s) with the most desirable channelcharacteristics (e.g., the strongest beam in the first set and thestrongest beam in the second set).

In an aspect, UE 431 may transmit information associated with thestrongest beam in the first set of beams (e.g., beam₅ 405) and thestrongest beam in the second set of beams (e.g., beam₁₃ 413) to the mmWbase station 432. For example, the information may include one or morechannel characteristics and/or estimates associated with at least beam₅405 and beam₁₃ 413.

In an aspect, the beamforming capability may be an analog beamformingcapability. For example, the mmW base station 432 may have analogbeamforming capability that may allow the mmW base station 432 totransmit a single beam (e.g., beam₅ 405 along path 417) through oneavailable RF chain at a time. The term RF chain refers to a combinationof power amplifier, digital to analog converter, and a mixer whenreferring to the transmit side of a modem or to a combination of a lownoise amplifier, demixer, and an analog to digital converter whenreferring to the receiver side of a modem. In an aspect, the beamformingcapability may be a digital beamforming capability. For example, the mmWbase station 432 may have digital beamforming capability, correspondingto the same number of RF chains as the number of antennas, that mayallow the mmW base station 432 to concurrently transmit multiple beams(e.g., one or more of beams 401, 403, 405, 407, 409, 411, 413, or 415)by emitting electromagnetic energy in multiple directions at the expenseof peak gain. In an aspect, the beamforming capability may be a hybridbeamforming capability with the number of RF chains being more than oneand less than the number of antennas. For example, the mmW base station432 may have hybrid beamforming capability that may allow the mmW basestation 432 to transmit a beam from each of the RF chains of the mmWbase station 432. In an aspect, the beamforming capability may be anavailability of multiple antenna sub-arrays. For example, the UE 431 mayhave multiple antenna subarrays that allow the UE 431 to transmit beamsfrom each of the antenna sub-arrays in different directions (e.g., therespective directions of beams 419, 421, 423, 425) to overcome RFobstructions, such as a hand of the user of the UE 431 inadvertentlyblocking a path of a beam.

In another aspect, the beamforming capability may be that one device inthe mmW communication system 400 has a higher antenna switching speedthan another device in the mmW communication system 400. For example,the mmW base station 432 may have a higher antenna switching speed thanthe UE 431. In such example, the higher antenna switching speed of themmW base station 432 may be leveraged by configuring the mmW basestation 432 to scan different directions and/or sectors while the UE 431transmits a beam in a fixed direction. In another example, the UE 431may have a higher antenna switching speed than the mmW base station 432.In such example, the higher antenna switching speed of the UE 431 may beleveraged by configuring the UE 431 to scan different directions and/orsectors while the mmW base station 432 transmits a beam in a fixeddirection.

After an initial synchronization and discovery phase, beam tracking maybe performed by the UE 431 and/or the mmW base station 432 bytransmitting a signal (e.g., BRRS) using fine beam angles p (e.g.,angles within a narrow range), where an initial estimate of the channelcharacteristics associated with beams separated by the course beamangles θ (e.g., angles within a broad range) has already been obtainedby the UE 431 and/or the mmW base station 432. Beam tracking algorithmstypically use the course beam angles (e.g., θ) learned in the initialsynchronization and discovery period as an initial value (also referredto as a seed value) and to subsequently fine tune these angles within anarrow range over a period of time in which the dynamic range of theangles is smaller than θ. For example, ρ may be less than θ.

For example, UE 431 may receive a third set of beams associated with aBRRS and a fourth set of beams associated with the BRRS from the seconddevice. In an aspect, the third set of beams may include the beams 405(e.g., the strongest beam in the first set of beams) and at least onebeam adjacent to the beam₅ 405, and the fourth set of beams may includebeam₁₃ 413 and at least one beam adjacent to beam₁₃ 413. In one aspect,the third set of beams may be adjacent beams selected from the firstgroup of beams (e.g., as seen in FIG. 4B) as discussed infra withrespect to FIG. 4D. In a further aspect, the fourth set of beams may beadjacent beams selected from the second group of beams (e.g., as seen inFIG. 4C) as discussed infra with respect to FIG. 4E.

FIG. 4D illustrates a set of fine beams 445 that may be separated by theangle ρ, wherein ρ is less than θ. The group of beams 445 illustrated inFIG. 4D contains beam₅ 405 and adjacent beams beam₄ 404 and beam₆ 406.The number of beams illustrated in FIG. 4D is meant to be illustrative,and one of ordinary skill understands that more or fewer beams may beincluded in the group of beams without departing from the scope of thepresent disclosure.

FIG. 4E illustrates a set of fine beams 455 that are separated by theangle ρ, wherein ρ is less than θ. The group of beams 455 illustrated inFIG. 4E contains beam₁₃ 413 and adjacent beams beam₁₂ 412 and beam₁₄414. The number of beams illustrated in FIG. 4E is meant to beillustrative, and one of ordinary skill understands that more or fewerbeams may be included in the group of beams without departing from thescope of the present disclosure.

Referring again to FIG. 4A, UE 431 may determine a strongest beam (e.g.,beam_(n+a)) in the third set of beams (e.g., beams 404, 405, 406) and astrongest beam (e.g., beam_(v+b)) in the fourth set of beams (e.g.,beams 412, 413, 414). For example, the strongest beam in the third setof beams may be beam₆ 406 (e.g., beam_(n+a), where n=5 and a=1 in FIG.4A) and the strongest beam in the fourth set of beams may be beam₁₂ 412(e.g., beam_(v+b), where v=13 and b=−1 in FIG. 4A). In the particularexample illustrated in FIG. 4A, n=5, v=13, a=1, and b=−1. However, thevalues n, v, a, and b are not limited to those illustrated in FIG. 4A.For example, the strongest beam in the third set of beams (e.g.,beam_(n+a)) may not be directly adjacent to the strong beam in the firstset of beams (e.g., beam_(n)) in which case a may be an integer valuegreater than 1 or an integer value less than−1. Similarly, the strongestbeam in the fourth set of beams (e.g., beam_(v+b)) may not be directlyadjacent to the strong beam in the second set of beams (e.g., beam_(v))in which case b may be an integer value greater than 1 or an integervalue less than−1.

In an aspect, UE 431 may transmit information associated with thestrongest beams in the third set of beams and the fourth set of beams tothe mmW base station 432. In one aspect, the information may beindicated by two bits in a message transmitted to the mmW base station432.

Due to the potentially large number of antenna ports at an mmW basestation and antenna subarrays at a UE the number of possible beams(e.g., beams with different beam angles) that may need to be scannedduring beam tracking may be quite large (e.g., a much larger number thanthe illustrated in the example described with respect to FIG. 4A)especially when a control channel and an associated data channel aretransmitted using different beams. Beam tracking a large number ofpotential channels may take an undesirable amount of time and createsignificant beam overhead. There is a need for a beam tracking techniquethat reduces the time needed to perform a beamforming procedure and thatreduces beam overhead.

The present disclosure provides a solution to the problem by providing arelationship between the control channel beam and the associated datachannel beam in order to reduce the time needed to complete beamtracking. In a first aspect, the control channel beam and the associateddata channel beam may be correlated via an explicit mapping or animplicit mapping of the different beams. In a second aspect, therelationship between the control channel beam and the associated datachannel beam may be independent without an explicit or implicit mapping.In the second aspect, the control channel beam and the associated datachannel beam may be selected without a correlation. By providing arelationship between the control channel beam and the associated datachannel beam, the present disclosure may reduce the time needed tocomplete beam tracking and reduce the beam overhead of the system bydecreasing the number of potential beams that may need to be scannedsince the UE 431 and/or mmW base station 432 may only need to determinean access beam for one of the control channel or the data channel.

FIG. 4F is a diagram of the mmW communication system 465 that may enablea reduction in the time needed to complete beam tracking and a reductionin beam overhead by providing a relationship between a first beam usedfor communicating a control channel and a second beam used forcommunicating an associated data channel. For example, the beam trackingprocedure described with respect to FIG. 4F may be performed with anexplicit or an implicit knowledge of a relationship between the controlchannel beam and the data channel beam in order to decrease the timeneeded to complete beamforming. In one aspect, the relationship may be acorrelation between the control channel beam and the data channel beam.In another configuration, the relationship between the control channelbeam and the data channel beam may be an independent relationship (e.g.,no apparent correlation between the control channel beam and the datachannel beam). In the second configuration, the relationship may bespecifically indicated via signaling.

Referring to FIG. 4F, the wireless communication system 465 may include,for example, a first device 434 and a second device 436 that performbeam tracking 485 (e.g., as described supra with respect to FIG. 4A) todetermine a first beam used for a first type of channel (e.g., controlchannel or data channel). The second beam used for the second type ofchannel (e.g., control channel or data channel) may be determined basedon a relationship with the first beam. In one aspect, the first beam andthe second beam may be different. In another aspect, the first beam andthe second beam may be the same beam. In further aspect, the firstchannel type and the second channel type may be different.

In one configuration, the first device 434 may be the UE 431 seen inFIG. 4A and the second device 436 may be the mmW base station 432 seenin FIG. 4A. In another configuration, the first device 434 may be themmW base station 432 seen in FIG. 4A and the second device 436 may bethe UE 431 seen in FIG. 4A.

First Example Embodiment

In a first example embodiment, first device 434 may determine a mappingbetween the first beam and the second beam by determining 440 that thefirst beam and the second beam differ in width by a first amount. In oneconfiguration, the first device 434 may know a priori the difference inwidth. In another configuration, the first device 434 may receive anindication 450 that the first beam and the second beam differ in widthby the fixed amount.

Based on the beam tracking procedure described supra with respect toFIG. 4A, the first device 434 and/or the second device 436 maydetermine, for example, that beam₁₃ 413 has the most desirable channelcharacteristics and will be used as the beam used for transmitting oneof the control channel or the data channel. The first device 434 maydetermine that beam₁₃ 413 and beam 427 (e.g., as seen in FIG. 4A) differin width by the fixed amount, and thus select beam 427 for transmittingthe other one of the control channel or the data channel.

Second Example Embodiment

In a second example embodiment, first device 434 may determine themapping by determining 440 that the first beam and the second beam arethe same beam. In one configuration, the first device 434 may know apriori that the same beam will be used for the first beam and the secondbeam. Optionally, the first device 434 may receive an indication 450that the same beam will be used for transmitting the control channel andthe data channel.

For example, one of the beams 401, 403, 405, 407, 409, 411, 413, 415that were used for transmitting BRS in FIG. 4A may be used for thecontrol channel and the data channel, or one of the beams 404, 405, 406,412, 413, 414 that were used for transmitting BRRS in FIG. 4A may beused for the control channel and the data channel.

Third Example Embodiment

In a third example embodiment, first device 434 may determine themapping by determining 440 that a first subarray associated with thefirst beam is quasi co-located with a second subarray associated withthe second beam.

Based on the beam tracking procedure described supra with respect toFIG. 4A, the first device 434 and/or the second device 436 maydetermine, for example, that beam₁₃ 413 has the most desirable channelcharacteristics and will be used for either the control channel 462 orthe data channel 464. The first device 434 may determine that thesubarray (e.g., antenna subarray if first device 434 is a UE and antennaports if first device 434 is an mmW base station) used for receivingbeam₁₃ 413 is quasi co-located with the subarray used for receivingbeam₂₇ 427, and thus select beam₂₇ 427 for the other one of the controlchannel 462 or the data channel 464.

When two subarrays are quasi co-located, the large-scale properties ofthe channel over which a symbol on one antenna port is conveyed can beinferred from the channel over which a symbol on the other antenna portis conveyed. For example, the large-scale properties may include one ormore of delay spread, Doppler spread, Doppler shift, average gain, andaverage delay.

Fourth Example Embodiment

In a fourth example embodiment, first device 434 may determine themapping by correlating 440 one of the BRS beams used as either thecontrol channel 462 or the data channel 464 with one of the BRRS beamsused as the other one of the control channel 462 or the data channel.

For example, beam, (e.g., beams in FIG. 4A) may be correlated withbeam_(n+a) (e.g., beam₆ in FIG. 4A) and beam_(v) (e.g., beam₁₃ in FIG.4A) may be correlated with beam_(v+b) (e.g., beam₁₂ in FIG. 4A), wherebeam_(n) and beam_(n+a) are both used to transmit the BRS, and beam_(v)and beam_(v+b) are both used to transmit the BRRS.

Optionally, the first device 434 may receive, from the second device436, an indication 450 that the beam_(n) is correlated with thebeam_(n+a) and/or beam_(v) is correlated with the beam_(v+b). In oneaspect, the indication 450 may be received via control channel (e.g.,PDCCH) signaling or RRC signaling. Additionally, the first device 434may receive, from the second device 436, information 450 indicating thatbeam_(n) (e.g., or beam_(v)) will be used for either the control channel462 or the data channel 464.

In a first configuration, the first device 434 may determine 440 thatbeam_(n+a) (e.g., beam₆ 406 in FIG. 4A) may be used for either thecontrol channel 462 or the data channel 464 when the beam_(n) (e.g.,beam₅ 405 in FIG. 4A) is used for the other one of the control channel462 or the data channel 464. Alternatively, in the first configuration,the first device 434 may determine that beam_(v+b) (e.g., beam₁₂ 412 inFIG. 4A) may be used for either the control channel 462 or the datachannel 464 when the beam_(v) (e.g., beam₁₃ 413 in FIG. 4A) is used asthe other one of the control channel 462 or the data channel 464.

In a second configuration, the first device 434 may determine 440 thatbeam_(n) (e.g., beam₅ 405 in FIG. 4A) may be used for either the controlchannel 462 or the data channel 464 when the beam_(n+a) (e.g., beam₆ 406in FIG. 4A) is used as the other one of the control channel 462 or thedata channel 464. Alternatively, in the second configuration, the firstdevice 434 may determine 440 that beam_(v) (e.g., beam₁₃ 413 in FIG. 4A)may be used for either the control channel 462 or the data channel 464when the beam_(v+b) (e.g., beam₁₂ 412 in FIG. 4A) is used as the otherone of the control channel 462 or the data channel 464.

Additionally and/or alternatively, first device 434 may receiveinformation 450 from the second device 436 indicating that beam_(n) willbe used for either the control channel 462 or the data channel and/orbeam_(v) will be used for the control channel 462 or data channel 464.

Fifth Example Embodiment

In a fifth example embodiment, first device 434 may determine themapping by correlating 440 one of the BRS beams used as the controlchannel with another one of the BRS beams used as the data channel.Additionally and/or alternatively, first device 434 may determine themapping by correlating 440 one of the BRRS beams used as the controlchannel with another one of the BRRS beams used as the data channel.

For example, beam_(n) (e.g., beam₅ 405 in FIG. 4A) may be correlatedwith beam_(v) (e.g., beam1₃ 413 in FIG. 4A) and beam_(n+a) (e.g., beam₆406 in FIG. 4A) may be correlated with beam_(v+b) (e.g., beam₁₂ 412 inFIG. 4A). For example, beam_(n) and beam_(v) may both used to transmitthe BRS and beam_(n+a) and beam_(v+b) are both used to transmit theBRRS.

In one configuration, the first device 434 may determine that beam_(v)will be used as either the control channel 462 or the data channel 464when beam_(n) is used the other one of the control channel 462 or thedata channel 464. Alternatively, the first device 434 may determine thatbeam_(v+b) will be used as either the control channel 462 or the datachannel 464 when beam_(n+a) is used the other one of the control channel462 or the data channel 464.

Sixth Example Embodiment

In a sixth example embodiment, the first device 434 may determine themapping by determining that beam_(x) will be used as the first beam andthat beam_(z) will be used as the second beam. For example, the firstdevice 434 may receive, from the second device, 436 information 450indicating that beam_(x) will be used as the first beam and thatbeam_(z) will be used as the second beam. Beam_(x) and beam_(z) may notbe correlated in any obvious manner, and thus the mapping in the sixthexample embodiment may be an independent relationship determined by thesecond device 436.

After determining 440 the relationship between the first beam and thesecond beam based on one example embodiments discussed supra, the firstdevice 434 may receive the control channel 462 and the data channel 464.

By providing the relationship between the control channel beam and theassociated data channel beam as described supra with respect to thefirst, second, third, fourth, fifth, and sixth example embodiments, thepresent disclosure may reduce the time needed to complete beam trackingand reduce the beam overhead of the system by decreasing the number ofpotential beams that may need to be scanned since the UE and/or mmW mayonly need to determine an access beam for one of the control channel orthe data channel.

FIGS. 5A-5C are a flowchart 500 of a method of wireless communication.The method may be performed by a first device (e.g., the UE 431, mmWbase station 432, first device 434, the apparatus 602/602′). In FIGS.5A-5C, operations indicated with dashed lines represent optionaloperations for various aspects of the disclosure.

Referring to FIG. 5A, at 502, the first device may receive a first setof beams associated with a BRS and a second set of beams associated withthe BRS. In an aspect, the first set of beams may be different than thesecond set of beams. For example, referring to FIG. 4A, during initialsynchronization, UE 431 may receive a signal (e.g., a BRS) in a firstset of beams (e.g., beams 401, 403, 405, 407) during a first symbol of asynchronization subframe and transmit the same signal in a second set ofbeams (e.g., beams 409, 411, 413, 415) during a second symbol of thesynchronization subframe.

At 504, the first device may determine a strongest beam in the first setof beams and a strongest beam in the second set of beams. In one aspect,the strongest beam in the first set of beams may be beam_(n) and thestrongest beam in the second set of beams may be beam_(v). For example,referring to FIG. 4A, UE 431 may determine a strongest beam (e.g.,beam_(n)) in the first set of beams and a strongest beam (e.g.,beam_(v)) in the second set of beams. For example, beam_(n) may be beam₅405 and beam_(v) may be beam₁₃ 413. In the particular exampleillustrated in FIG. 4A, n=5 and v=13. However, the values n and v arenot limited to those illustrated in FIG. 4A.

At 506, the first device may transmit information associated with thestrongest beam in the first set of beams and the strongest beam in thesecond set of beams to the second device. For example, referring to FIG.4A, UE 431 may transmit information associated with the strongest beamin the first set of beams (e.g., beam₅ 405) and the strongest beam inthe second set of beams (e.g., beam₁₃ 413) to the mmW base station 432.For example, the information may include one or more channelcharacteristics and/or estimates associated with at least beam₅ 405 andbeam₁₃ 413.

At 508, the first device may receive a third set of beams associatedwith a BRRS and a fourth set of beams associated with the BRRS from thesecond device. In one aspect, the third set of beams may include thebeam_(n) and at least one beam adjacent to the beam_(n), and the fourthset of beams may include the beam_(v) and at least one beam adjacent tothe beam_(v). For example, referring to FIG. 4A, UE 431 may receive athird set of beams associated with a BRRS and a fourth set of beamsassociated with the BRRS from the second device. In an aspect, the thirdset of beams may include the beam₅ 405 (e.g., beam_(n)) and at least onebeam adjacent to the beam₅ 405, and the fourth set of beams may includebeam₁₃ 413 (e.g., beam_(v)) and at least one beam adjacent to beam₁₃413. In one aspect, the third set of beams (e.g., discussed supra withrespect to FIG. 4D) may be adjacent beams selected from the first groupof beams in FIG. 4B In a further aspect, the fourth set of beams (e.g.,discussed supra with respect to FIG. 4E) may be adjacent beams selectedfrom the second group of beams in FIG. 4C.

At 510, the first device may determine a strongest beam in the third setof beams and a strongest beam in the fourth set of beams. In an aspect,the strongest beam in the third set of beams may be beam_(n+a) and thestrongest beam in the fourth set of beams may be beam_(v+b). Forexample, referring to FIG. 4A, UE 431 may determine a strongest beam(e.g., beam_(n+a)) in the third set of beams (e.g., beams 404, 405, 406)and a strongest beam (e.g., beam_(v+b)) in the fourth set of beams(e.g., beams 412, 413, 414). For example, the strongest beam in thethird set of beams may be beam₆ 406 (e.g., beam_(n+a), where n=5 and a=1in FIG. 4A) and the strongest beam in the fourth set of beams may bebeam₁₂ 412 (e.g., beam_(v+b), where v=13 and b=−1 in FIG. 4A). In theparticular example illustrated in FIG. 4A, n=5, v=13, a=1, and b=−1.However, the values n, v, a, and b are not limited to those illustratedin FIG. 4A. For example, the strongest beam in the third set of beams(e.g., beam_(n+a)) may not be directly adjacent to the strong beam inthe first set of beams (e.g., beam_(n)) in which case a may be aninteger value greater than 1 or an integer value less than−1. Similarly,the strongest beam in the fourth set of beams (e.g., beam_(v+b)) may notbe directly adjacent to the strong beam in the second set of beams(e.g., beam_(v)) in which case b may be an integer value greater than 1or an integer value less than−1.

At 512, the first device may transmit information associated with thestrongest beam in the third set of beams and the strongest beam in thefourth set of beams to the second device. For example, referring to FIG.4A, UE 431 may transmit information associated with the strongest beamsin the third set of beams and the fourth set of beams to the mmW basestation 432. In one aspect, the information may be indicated by two bitsin a message transmitted to the mmW base station 432.

At 514, the first device may receive, from the second device,information indicating that either beam_(n) or beam_(v) will be used asthe first beam associated with the first type of channel. For example,referring to FIG. 4F, the first device 434 may receive, from the seconddevice 436, information 450 indicating that beam_(n) (e.g., or beam_(v))will be used for the control channel 462 or the data channel 464.

At 516, the first device may receive, from the second device, anindication that the first beam and the second beam differ in width bythe fixed amount. For example, referring to FIG. 4F, the first device434 may receive an indication 450 that the first beam and the secondbeam differ in width by the fixed amount.

Referring to FIG. 5B, at 518, the first device may determine a mappingbetween a first beam associated with a first type of channel and asecond beam associated with a second type of channel. In one aspect, thefirst type of channel may be different than the second type of channel.For example, the first type of channel may be a control channel and thesecond type of channel may be a data channel, or vice versa. Referringto FIG. 4F, a first device 434 and/or a second device 436 may performbeam tracking 485 (e.g., as described supra with respect to FIG. 4A) todetermine a first beam used for a first type of channel (e.g., controlchannel or data channel) and/or a second beam used for a second type ofchannel (e.g., control channel or data channel). The second beam usedfor the second type of channel may be determined based on a relationshipwith the first beam. In one aspect, the first beam and the second beammay be different. In another aspect, the first beam and the second beammay be the same beam. In further aspect, the first channel type and thesecond channel type may be different. For example, the first channeltype may be a control channel an the second channel type may be anassociated data channel, or vice versa.

First Example Embodiment

At 520, the first device may determine the mapping by determining thatthe first beam and the second beam differ in width by a fixed amount.For example, referring to FIG. 4F, first device 434 may determine amapping between the first beam and the second beam by determining 440that the first beam and the second beam differ in width by a firstamount. In one configuration, the first device 434 may know a priori thedifference in width. In another configuration, the first device 434 mayreceive an indication 450 that the first beam and the second beam differin width by the fixed amount. Based on the beam tracking proceduredescribed supra with respect to FIG. 4A, the first device 434 and/or thesecond device 436 may determine, for example, that beam₁₃ 413 has themost desirable channel characteristics and will be used as the beam usedfor transmitting one of the control channel or the data channel. Thefirst device 434 may determine that beam₁₃ 413 and beam₂₇ 427 (e.g., asseen in FIG. 4A) differ in width by the fixed amount, and thus selectbeam₂₇ 427 for transmitting the other one of the control channel or thedata channel.

At 522, the first device may determine the mapping by determining beamswill be used as the first beam associated with the first type of channelwhen beam_(n) is used as the second beam associated with the second typeof channel. In an aspect, the beam_(z) and the beam_(n) may differ inwidth by the fixed amount. For example, referring to FIGS. 4A and 4F,based on the beam tracking procedure, the first device 434 and/or thesecond device 436 may determine, for example, that beam₁₃ 413 has themost desirable channel characteristics and will be used as the beam usedfor transmitting one of the control channel or the data channel. Thefirst device 434 may determine that beam₁₃ 413 and beam₂₇ 427 (e.g., asseen in FIG. 4A) differ in width by the fixed amount, and thus selectbeam₂₇ 427 for transmitting the other one of the control channel or thedata channel. In this particular example, n=13 and z=27. However, thevalues for n and z are not limited to 13 and 27, respectively.

Second Example Embodiment

At 524, the first device may determine that a same beam will be used asthe first beam and the second beam. For example, referring to FIGS. 4Aand 4F, first device 434 may determine the mapping by determining 440that the first beam and the second beam are the same beam. In oneconfiguration, the first device 434 may know a priori that the same beamwill be used for the first beam and the second beam. Optionally, thefirst device 434 may receive an indication 450 that the same beam willbe used for transmitting the control channel and the data channel. Forexample, one of the beams 401, 403, 405, 407, 409, 411, 413, 415 thatwere used for transmitting BRS in FIG. 4A may be used for the controlchannel and the data channel, or one of the beams 404, 405, 406, 412,413, 414 that were used for transmitting BRRS in FIG. 4A may be used forthe control channel and the data channel.

Third Example Embodiment

At 526, the first device may determine the mapping by determining that afirst subarray associated with the first beam is quasi co-located with asecond subarray associated with the second beam. For example, referringto FIGS. 4A and 4F, the first device 434 and/or the second device 436may determine, for example, that beam₁₃ 413 has the most desirablechannel characteristics and will be used for transmitting either thecontrol channel 462 or the data channel 464. The first device 434 maydetermine that the subarray (e.g., antenna subarray if first device 434is a UE and antenna ports if first device 434 is an mmW base station)used for receiving beam₁₃ 413 is quasi co-located with the subarray usedfor receiving beam₂₇ 427, and thus select beam₂₇ 427 for the other oneof the control channel 462 or the data channel 464.

At 528, the first device may determine beams will be used as the firstbeam associated with the first type of channel when beam_(n) is used asthe second beam associated with the second type of channel based on thefirst subarray being quasi co-located with the second subarray. Forexample, referring to FIG. 4F, The first device 434 may determine thatthe subarray (e.g., antenna subarray if first device 434 is a UE andantenna ports if first device 434 is an mmW base station) used forreceiving beam₁₃ 413 is quasi co-located with the subarray used forreceiving beam₂₇ 427, and thus select beam₂₇ 427 for the other one ofthe control channel 462 or the data channel 464. In this particularexample, n=13 and z=27. However, the values for n and z are not limitedto 13 and 27, respectively.

Fourth Example Embodiment

At 530, the first device may receive, from the second device, anindication that the beam_(n) is correlated with the beam_(n+a) and thebeam_(v) is correlated with the beam_(v+b). For example, referring toFIG. 4F, the first device 434 may receive, from the second device 436,an indication 450 that the beam_(n) is correlated with the beam_(n+a)and/or beam_(v) is correlated with the bean_(v+b). In one aspect, theindication 450 may be received via control channel (e.g., PDCCH)signaling or RRC signaling.

At 532, the first device may determine the mapping by determining afirst correlation between the beam_(n) and the beam_(n+a) and a secondcorrelation between the beam with the beam_(v+b). For example, referringto FIG. 4F, first device 434 may determine the mapping by correlating440 one of the BRS beams used as either the control channel 462 or thedata channel 464 with one of the BRRS beams used as the other one of thecontrol channel 462 or the data channel. For example, beam_(n) (e.g.,beam₅ in FIG. 4A) may be correlated with beam_(v+b) (e.g., beam₆ in FIG.4A) and beam_(v) (e.g., beam₁₃ in FIG. 4A) may be correlated withbeam_(v+b) (e.g., beam₁₂ in FIG. 4A), where beam_(n) and beam_(n+a) areboth used to transmit the BRS, and beam_(v) and beam_(v+b) are both usedto transmit the BRRS.

At 534, the first device may determine that the beam_(n+a) will be usedas the second beam associated with the second type of channel when thebeam_(n) is used as the first beam associated with the first type ofchannel based on the correlation. For example, referring to FIG. 4F, Ina first configuration, the first device 434 may determine 440 thatbeam_(n+a) (e.g., beam₆ 406 in FIG. 4A) may be used for either thecontrol channel 462 or the data channel 464 when the beam_(n) (e.g.,beam₅ 405 in FIG. 4A) is used for the other one of the control channel462 or the data channel 464.

At 536, the first device may determine that the beam_(n) will be used asthe first beam associated with the first type of channel when thebeam_(n+a) is used as the second beam associated with the second type ofchannel based on the correlation. For example, referring to FIG. 4F, ina first configuration, the first device 434 may determine 440 thatbeam_(n+a) (e.g., beam₆ 406 in FIG. 4A) may be used for either thecontrol channel 462 or the data channel 464 when the beam_(n) (e.g.,beam₅ 405 in FIG. 4A) is used for the other one of the control channel462 or the data channel 464. Alternatively, in the first configuration,the first device 434 may determine that beam_(v+b) (e.g., beam₁₂ 412 inFIG. 4A) may be used for either the control channel 462 or the datachannel 464 when the beam_(v) (e.g., beam₁₃ 413 in FIG. 4A) is used asthe other one of the control channel 462 or the data channel 464. In asecond configuration, the first device 434 may determine 440 that beam,(e.g., beams 405 in FIG. 4A) may be used for either the control channel462 or the data channel 464 when the beam_(n+a) (e.g., beam₆ 406 in FIG.4A) is used as the other one of the control channel 462 or the datachannel 464. Alternatively, in the second configuration, the firstdevice 434 may determine 440 that beam_(v) (e.g., beam₁₃ 413 in FIG. 4A)may be used for either the control channel 462 or the data channel 464when the beam_(v+b) (e.g., beam₁₂ 412 in FIG. 4A) is used as the otherone of the control channel 462 or the data channel 464.

Fifth Example Embodiment

As seen in FIG. 5C, at 538, the first device may determine the mappingby determining a third correlation between the beam_(n) and the beam_(v)and a fourth correlation between the beam_(n+a) and the beam_(v+b). Forexample, referring to FIG. 4F, the first device 434 may determine themapping by correlating 440 one of the BRS beams used as the controlchannel with another one of the BRS beams used as the data channel.Additionally and/or alternatively, first device 434 may determine themapping by correlating 440 one of the BRRS beams used as the controlchannel with another one of the BRRS beams used as the data channel. Forexample, beam_(n) (e.g., beam₅ 405 in FIG. 4A) may be correlated withbeam_(v) (e.g., beam₁₃ 413 in FIG. 4A) and beam_(n+a) (e.g., beam₆ 406in FIG. 4A) may be correlated with beam_(v+b) (e.g., beam₁₂ 412 in FIG.4A). For example, beam, and beam, may both used to transmit the BRS andbeam_(n+a) and beam_(v−b) are both used to transmit the BRRS.

At 540, the first device may determine that the beam will be used as thesecond beam associated with the second type of channel when the beam_(n)is used as the first beam associated with the first type of channelbased on the correlation. For example, referring to FIG. 4F, the firstdevice 434 may determine that beam_(v) will be used as either thecontrol channel 462 or the data channel 464 when beam_(n) is used theother one of the control channel 462 or the data channel 464.Alternatively, the first device 434 may determine that beam_(n+b) willbe used as either the control channel 462 or the data channel 464 whenbeam_(n+a) is used the other one of the control channel 462 or the datachannel 464.

Sixth Example Embodiment

At 542, the first device may determine the mapping by determining thatbeam_(x) will be used as the first beam and that beam_(z) will be usedas the second beam. For example, referring to FIG. 4F, the first device434 may determine the mapping by determining that beam_(x) will be usedas the first beam and that beam_(z) will be used as the second beam.Beam_(x) and beam_(z) may not be correlated in any obvious manner, andthus the mapping in the sixth example embodiment may be an independentrelationship determined by the second device 436.

At 544, the first device may receive the first beam associated with thefirst type of channel and the second beam associated with the secondtype of channel. In an aspect, the first beam and the second beam may bereceived from a second device. For example, referring to FIG. 4F, afterdetermining 440 the relationship between the first beam and the secondbeam based on one example embodiments discussed supra, the first device434 may receive the control channel 462 and the data channel 464.

FIG. 6 is a conceptual data flow diagram 600 illustrating the data flowbetween different means/components in an example apparatus 602. Theapparatus may be a first device (e.g., first device 434, UE 104, 350,431, or mmW base station 180, 310, 432) in communication with a seconddevice 650 (e.g., second device 436, UE 104, 350, 431, or mmW basestation 180, 310, 432). The apparatus includes a reception component 604that may receive first set of beams associated with a BRS 601 and asecond set of beams associated with the BRS 601. In an aspect, the firstset of beams may be different than the second set of beams. Receptioncomponent 604 may transmit a signal 603 associated with the BRS 601 todetermination component 606. Determination component 606 may determine astrongest beam in the first set of beams and a strongest beam in thesecond set of beams. In one aspect, the strongest beam in the first setof beams may be beam_(n) and the strongest beam in the second set ofbeams may be beam_(v). Determination component 606 may send a signal 607associated with the strongest beam information (e.g., beam_(n) andbeam_(v)) to the transmission component 608. Transmission component 608may send a signal 609 associated with the strongest beam information forthe first and second sets of beams to the second device 650. Receptioncomponent 604 may receive a third set of beams associated with a BRRS601 and a fourth set of beams associated with the BRRS 601 from thesecond device 650. In one aspect, the third set of beams may include thebeam_(n) and at least one beam adjacent to the beam_(n), and the fourthset of beams may include the beam_(v) and at least one beam adjacent tothe beam_(v). Reception component may send a signal 603 associated withthe BRRS to determination component 606. Determination component 606 maydetermine a strongest beam in the third set of beams and a strongestbeam in the fourth set of beams. In an aspect, the strongest beam in thethird set of beams may be beam_(n+a) and the strongest beam in thefourth set of beams may be beam_(n+b). Determination component 606 maysend a signal associated with the strongest beam information for thethird and fourth set of beams (e.g., beam_(n+a) and beam_(v+b)) totransmission component 608. Transmission component 608 may send a signal609 associated with the strongest beam information for the third andfourth sets of beams to the second device 650. Reception component 604may receive information 601 indicating that either beam_(n) or beam_(v)will be used as the first beam associated with the first type of channelor the second beam associated with the second type of channel. Receptioncomponent 604 may receive mapping information 601 that indicates thatthe first beam and the second beam differ in width by the fixed amount.Reception component 604 may send a signal 603 associated with thedifference in beam width to the determination component 606.Determination component 606 may determine a mapping between a first beamassociated with a first type of channel and a second beam associatedwith a second type of channel. In one aspect, the first type of channelmay be different than the second type of channel. In one aspect, thedetermination component 606 may determine the mapping by determiningthat the first beam and the second beam differ in width by a fixedamount. In a first example embodiment, determination component 606 maydetermine the mapping by determining beams will be used as the firstbeam associated with the first type of channel when beam_(n) is used asthe second beam associated with the second type of channel. In anaspect, the beam_(z) and the beam_(n) may differ in width by the fixedamount. In a second example embodiment, determination component 606 maydetermine that a same beam will be used as the first beam and the secondbeam (e.g., based on a priori knowledge at the determination component606 or from a message from the second device 650). In a third exampleembodiment, determination component 606 may determine the mapping bydetermining that a first subarray associated with the first beam isquasi co-located with a second subarray associated with the second beam.For example, determination component 606 may determine beams will beused as the first beam associated with the first type of channel whenbeam_(n) is used as the second beam associated with the second type ofchannel based on the first subarray being quasi co-located with thesecond subarray. In a fourth example embodiment, reception component 604may receive, from the second device 650, an indication 601 (e.g.,mapping) that the beam_(n) is correlated with the beam_(n+a) and thebeam_(v) is correlated with the bean_(v+b). Reception component 604 maysend a signal 603 associated with the mapping to determination component606. Determination component 606 may determine the mapping bydetermining a first correlation between the beam_(n) and the beam_(n+a)and a second correlation between the beam_(v) with the bean_(v+b). Forexample, determination component 606 may determine that the beam_(n)will be used as the first beam associated with the first type of channelwhen the beam_(n+a) is used as the second beam associated with thesecond type of channel based on the correlation. In a fifth exampleembodiment, determination component 606 may determine the mapping bydetermining a third correlation between the beam_(n) and the beam_(v)and a fourth correlation between the beam_(n+a) and the bean_(v+b). Forexample, determination component 606 may determine that the beam_(v)will be used as the second beam associated with the second type ofchannel when the beam_(n) is used as the first beam associated with thefirst type of channel based on the correlation. In a sixth exampleembodiment, reception component 604 may receive information 601 (e.g.,independent mapping) indicating that beam), will be used as the firstbeam and that beams will be used as the second beam. Reception component604 may send a signal 603 associated with the independent mapping todetermination component 606. Determination component 606 may determinethat beam will be used as the first beam and that beam_(z) will be usedas the second beam. Information 605 associated with the determined beamsfor the control channel and the data channel determined in the first,second, third, fourth, fifth, and sixth example embodiments may be sentto reception component 604. Reception component 604 may then receive thecontrol channel in one beam and the associated data channel 601 in adifferent beam.

The apparatus may include additional components that perform each of theblocks of the algorithm in the aforementioned flowcharts of FIGS. 5A-5C.As such, each block in the aforementioned flowcharts of FIGS. 5A-5C maybe performed by a component and the apparatus may include one or more ofthose components. The components may be one or more hardware componentsspecifically configured to carry out the stated processes/algorithm,implemented by a processor configured to perform the statedprocesses/algorithm, stored within a computer-readable medium forimplementation by a processor, or some combination thereof.

FIG. 7 is a diagram 700 illustrating an example of a hardwareimplementation for an apparatus 602′ employing a processing system 714.The processing system 714 may be implemented with a bus architecture,represented generally by the bus 724. The bus 724 may include any numberof interconnecting buses and bridges depending on the specificapplication of the processing system 714 and the overall designconstraints. The bus 724 links together various circuits including oneor more processors and/or hardware components, represented by theprocessor 704, the components 604, 606, 608, and the computer-readablemedium/memory 706. The bus 724 may also link various other circuits suchas timing sources, peripherals, voltage regulators, and power managementcircuits, which are well known in the art, and therefore, will not bedescribed any further.

The processing system 714 may be coupled to a transceiver 710. Thetransceiver 710 is coupled to one or more antennas 720. The transceiver710 provides a means for communicating with various other apparatus overa transmission medium. The transceiver 710 receives a signal from theone or more antennas 720, extracts information from the received signal,and provides the extracted information to the processing system 714,specifically the reception component 604. In addition, the transceiver710 receives information from the processing system 714, specificallythe transmission component 608, and based on the received information,generates a signal to be applied to the one or more antennas 720. Theprocessing system 714 includes a processor 704 coupled to acomputer-readable medium/memory 706. The processor 704 is responsiblefor general processing, including the execution of software stored onthe computer-readable medium/memory 706. The software, when executed bythe processor 704, causes the processing system 714 to perform thevarious functions described supra for any particular apparatus. Thecomputer-readable medium/memory 706 may also be used for storing datathat is manipulated by the processor 704 when executing software. Theprocessing system 714 further includes at least one of the components604, 606, 608. The components may be software components running in theprocessor 704, resident/stored in the computer readable medium/memory706, one or more hardware components coupled to the processor 704, orsome combination thereof. The processing system 714 may be a componentof the UE 350 and may include the memory 360 and/or at least one of theTX processor 368, the RX processor 356, and the controller/processor359.

In one configuration, the apparatus 602/602′ for wireless communicationmay include means for determining a mapping between a first beamassociated with a first type of channel and a second beam associatedwith a second type of channel. In an aspect, the first type of channelmay be different than the second type of channel. In an aspect, thefirst type of channel is one of a control channel or a data channel andthe second type of channel is the other one of the control channel orthe data channel. In another configuration, the apparatus 602/602′ forwireless communication may include means for receiving, from the seconddevice, an indication that the first beam and the second beam differ inwidth by the fixed amount. In a first configuration, the means fordetermining the mapping may be configured to determine that the firstbeam and the second beam differ in width by a fixed amount. For example,the means for determining the mapping may be configured to determinebeam_(z) will be used as the first beam associated with the first typeof channel when beam_(n) is used as the second beam associated with thesecond type of channel. In an aspect, the beam_(z) and the beam_(n) maydiffer in width by the fixed amount. In another configuration, the meansfor determining the mapping may be configured to determine that a samebeam will be used as the first beam and the second beam. In a furtherconfiguration, the means for determining the mapping may be configuredto determine that a first subarray associated with the first beam isquasi co-located with a second subarray associated with the second beam.For example, the means for determining the mapping may be configured todetermine beam_(n) will be used as the first beam associated with thefirst type of channel when beam_(z) is used as the second beamassociated with the second type of channel based on the first subarraybeing quasi co-located with the second subarray. In a furtherconfiguration, the apparatus 602/602′ for wireless communication mayinclude means for receiving a first set of beams associated with a BRSand a second set of beams associated with the BRS. In an aspect, thefirst set of beams may be different than the second set of beams. Inanother configuration, the apparatus 602/602′ for wireless communicationmay include means for determining a strongest beam in the first set ofbeams and a strongest beam in the second set of beams. In an aspect, thestrongest beam in the first set of beams may be beam_(n) and thestrongest beam in the second set of beams may be beam_(v). In a furtherconfiguration, the apparatus 602/602′ for wireless communication mayinclude means for receiving a third set of beams associated with a BRRSand a fourth set of beams associated with the BRRS from the seconddevice. In one aspect, the third set of beams may include the beam_(n)and at least one beam adjacent to the beam_(n), and the fourth set ofbeams may include the beam_(v) and at least one beam adjacent to thebeam_(v). In one configuration, the apparatus 602/602′ for wirelesscommunication may include means for determining a strongest beam in thethird set of beams and a strongest beam in the fourth set of beams. Inan aspect, the strongest beam in the third set of beams may bebeam_(n+a) and the strongest beam in the fourth set of beams may bebeam_(v+b). In another configuration, the apparatus 602/602′ forwireless communication may include means for transmitting informationassociated with the strongest beam in the third set of beams and thestrongest beam in the fourth set of beams to the second device. In anaspect, the means for determining the mapping is configured to determinea first correlation between the beam_(n) and the beam_(n+a) and a secondcorrelation between the beam with the beam_(v+b), and/or determine athird correlation between the beam_(n) and the beam_(v) and a fourthcorrelation between the beam_(n+a) and the bean_(v+b). In oneconfiguration, the apparatus 602/602′ for wireless communication mayinclude means for receiving, from the second device, informationassociated with at least one of the first correlation, the secondcorrelation, the third correlation, or the fourth correlation. In anaspect, the information may be received via control channel signaling orRRC signaling. In an aspect, the means for determining the mapping maybe configured to determine that the beam_(n+a) will be used as thesecond beam associated with the second type of channel when the beam_(n)is used as the first beam associated with the first type of channelbased on the correlation. In another aspect, the means for determiningthe mapping may be configured to determine that the beam_(v) will beused as the second beam associated with the second type of channel whenthe beam_(n) is used as the first beam associated with the first type ofchannel based on the correlation. In a further aspect, the means fordetermining the mapping may be configured to determine that that thebeam_(n) will be used as the first beam associated with the first typeof channel when the beam_(n+a) is used as the second beam associatedwith the second type of channel based on the correlation. In stillanother aspect, the means for determining the mapping may be configuredto determining that beam_(x) will be used as the first beam and thatbeam_(z) will be used as the second beam. In one configuration, thefirst device may be a UE and the second device may be a mmW basestation. In another configuration, the first device may be a mmW basestation and the second device may be a UE. The aforementioned means maybe one or more of the aforementioned components of the apparatus 602and/or the processing system 714 of the apparatus 602′ configured toperform the functions recited by the aforementioned means. As describedsupra, the processing system 714 may include the TX Processor 368, theRX Processor 356, and the controller/processor 359. As such, in oneconfiguration, the aforementioned means may be the TX Processor 368, theRX Processor 356, and the controller/processor 359 configured to performthe functions recited by the aforementioned means.

It is understood that the specific order or hierarchy of blocks in theprocesses/flowcharts disclosed is an illustration of example approaches.Based upon design preferences, it is understood that the specific orderor hierarchy of blocks in the processes/flowcharts may be rearranged.Further, some blocks may be combined or omitted. The accompanying methodclaims present elements of the various blocks in a sample order, and arenot meant to be limited to the specific order or hierarchy presented.

The previous description is provided to enable any person skilled in theart to practice the various aspects described herein. Variousmodifications to these aspects will be readily apparent to those skilledin the art, and the generic principles defined herein may be applied toother aspects. Thus, the claims are not intended to be limited to theaspects shown herein, but is to be accorded the full scope consistentwith the language claims, wherein reference to an element in thesingular is not intended to mean “one and only one” unless specificallyso stated, but rather “one or more.” The word “exemplary” is used hereinto mean “serving as an example, instance, or illustration.” Any aspectdescribed herein as “exemplary” is not necessarily to be construed aspreferred or advantageous over other aspects. Unless specifically statedotherwise, the term “some” refers to one or more. Combinations such as“at least one of A, B, or C,” “one or more of A, B, or C,” “at least oneof A, B, and C,” “one or more of A, B, and C,” and “A, B, C, or anycombination thereof” include any combination of A, B, and/or C, and mayinclude multiples of A, multiples of B, or multiples of C. Specifically,combinations such as “at least one of A, B, or C,” “one or more of A, B,or C,” “at least one of A, B, and C,” “one or more of A, B, and C,” and“A, B, C, or any combination thereof” may be A only, B only, C only, Aand B, A and C, B and C, or A and B and C, where any such combinationsmay contain one or more member or members of A, B, or C. All structuraland functional equivalents to the elements of the various aspectsdescribed throughout this disclosure that are known or later come to beknown to those of ordinary skill in the art are expressly incorporatedherein by reference and are intended to be encompassed by the claims.Moreover, nothing disclosed herein is intended to be dedicated to thepublic regardless of whether such disclosure is explicitly recited inthe claims. The words “module,” “mechanism,” “element,” “device,” andthe like may not be a substitute for the word “means.” As such, no claimelement is to be construed as a means plus function unless the elementis expressly recited using the phrase “means for.”

What is claimed is:
 1. A method of wireless communication for a firstdevice, comprising: determining a mapping between a first beamassociated with a first type of channel and a second beam associatedwith a second type of channel, the first type of channel being differentthan the second type of channel; and receiving the first beam associatedwith the first type of channel and the second beam associated with thesecond type of channel, the first beam and the second beam beingreceived from a second device.
 2. The method of claim 1, wherein thefirst type of channel is one of a control channel or a data channel andthe second type of channel is the other one of the control channel orthe data channel.
 3. The method of claim 1, wherein the determining themapping comprises: determining that the first beam and the second beamdiffer in width by a fixed amount.
 4. The method of claim 3, furthercomprising: receiving, from the second device, an indication that thefirst beam and the second beam differ in width by the fixed amount. 5.The method of claim 3, wherein the determining the mapping furthercomprises: determining beam_(z) will be used as the first beamassociated with the first type of channel when beam_(n) is used as thesecond beam associated with the second type of channel, the beam_(z) andthe beam_(n) differing in width by the fixed amount.
 6. The method ofclaim 1, wherein the determining the mapping comprises: determining thata same beam will be used as the first beam and the second beam.
 7. Themethod of claim 1, wherein the determining the mapping comprises:determining that a first subarray associated with the first beam isquasi co-located with a second subarray associated with the second beam.8. The method of claim 7, wherein the determining the mapping furthercomprises: determining beam_(n) will be used as the first beamassociated with the first type of channel when beam_(z) is used as thesecond beam associated with the second type of channel based on thefirst subarray being quasi co-located with the second subarray.
 9. Themethod of claim 1, further comprising: receiving a first set of beamsassociated with a beam reference signal (BRS) and a second set of beamsassociated with the BRS, the first set of beams being different than thesecond set of beams; determining a strongest beam in the first set ofbeams and a strongest beam in the second set of beams, the strongestbeam in the first set of beams being beam_(n) and the strongest beam inthe second set of beams being beam_(v); and transmitting informationassociated with the strongest beam in the first set of beams and thestrongest beam in the second set of beams to the second device.
 10. Themethod of claim 9, further comprising: receiving a third set of beamsassociated with a beam refinement reference signal (BRRS) and a fourthset of beams associated with the BRRS from the second device, the thirdset of beams including the beam_(n) and at least one beam adjacent tothe beam_(n), and the fourth set of beams including the beam and atleast one beam adjacent to the beam_(v); determining a strongest beam inthe third set of beams and a strongest beam in the fourth set of beams,the strongest beam in the third set of beams being beam_(n+a) and thestrongest beam in the fourth set of beams being beam_(v+b); andtransmitting information associated with the strongest beam in the thirdset of beams and the strongest beam in the fourth set of beams to thesecond device.
 11. The method of claim 10, wherein the determining themapping comprises: determining a first correlation between the beam_(n)and the beam_(n+a) and a second correlation between the beam_(v) withthe beam_(v+b); or determining a third correlation between the beam_(n)and the beam_(v) and a fourth correlation between the beam_(n+a) and thebeam_(v+b).
 12. The method of claim 11, wherein the determining themapping further comprises: receiving, from the second device,information associated with at least one of the first correlation, thesecond correlation, the third correlation, or the fourth correlation.13. The method of claim 12, wherein the information is received viacontrol channel signaling or radio resource control (RRC) signaling. 14.The method of claim 11, wherein the determining the mapping furthercomprises: determining that the beam_(n+a) will be used as the secondbeam associated with the second type of channel when the beam_(n) isused as the first beam associated with the first type of channel basedon the first correlation.
 15. The method of claim 11, wherein thedetermining the mapping further comprises: determining that the beam_(v)will be used as the second beam associated with the second type ofchannel when the beam_(n) is used as the first beam associated with thefirst type of channel based on the third correlation.
 16. The method ofclaim 11, wherein the determining the mapping further comprises:determining that the beam_(n) will be used as the first beam associatedwith the first type of channel when the beam_(n+a) is used as the secondbeam associated with the second type of channel based on the firstcorrelation.
 17. The method of claim 1, wherein the determining themapping comprises: determining that beam_(x) will be used as the firstbeam and that beam_(z) will be used as the second beam, beam_(x) andbeam_(z) being uncorrelated.
 18. The method of claim 1, wherein thefirst device is a user equipment and the second device is amillimeter-wave base station.
 19. The method of claim 1, wherein thefirst device is a millimeter-wave base station and the second device isa user equipment.
 20. An apparatus for wireless communication, theapparatus being a first device comprising: a memory; and at least oneprocessor coupled to the memory and configured to: determine a mappingbetween a first beam associated with a first type of channel and asecond beam associated with a second type of channel, the first type ofchannel being different than the second type of channel; and receive thefirst beam associated with the first type of channel and the second beamassociated with the second type of channel, the first beam and thesecond beam being received from a second device.
 21. The apparatus ofclaim 20, wherein the first type of channel is one of a control channelor a data channel and the second type of channel is the other one of thecontrol channel or the data channel.
 22. The apparatus of claim 20,wherein the at least one processor is configured to determine themapping by: determining that the first beam and the second beam differin width by a fixed amount.
 23. The apparatus of claim 20, wherein theat least one processor is configured to determine the mapping by:determining that a same beam will be used as the first beam and thesecond beam.
 24. The apparatus of claim 20, wherein the at least oneprocessor is configured to determine the mapping by: determining that afirst subarray associated with the first beam is quasi co-located with asecond subarray associated with the second beam.
 25. The apparatus ofclaim 20, wherein the at least one processor is further configured to:receive a first set of beams associated with a beam reference signal(BRS) and a second set of beams associated with the BRS, the first setof beams being different than the second set of beams; determine astrongest beam in the first set of beams and a strongest beam in thesecond set of beams, the strongest beam in the first set of beams beingbeam_(n) and the strongest beam in the second set of beams beingbeam_(v); and transmit information associated with the strongest beam inthe first set of beams and the strongest beam in the second set of beamsto the second device.
 26. The apparatus of claim 25, wherein the atleast one processor is further configured to: receive a third set ofbeams associated with a beam refinement reference signal (BRRS) and afourth set of beams associated with the BRRS from the second device, thethird set of beams including the beam_(n) and at least one beam adjacentto the beam_(n), and the fourth set of beams including the beam_(v) andat least one beam adjacent to the beam_(v); determine a strongest beamin the third set of beams and a strongest beam in the fourth set ofbeams, the strongest beam in the third set of beams being beam_(n+a) andthe strongest beam in the fourth set of beams being beam_(v+b); andtransmit information associated with the strongest beam in the third setof beams and the strongest beam in the fourth set of beams to the seconddevice.
 27. The apparatus of claim 26, wherein the at least oneprocessor is configured to determine the mapping by: determining a firstcorrelation between the beam_(n) and the beam_(n+a) and a secondcorrelation between the beam_(v) with the beam_(v+b); or determining athird correlation between the beam_(n) and the beam_(v) and a fourthcorrelation between the beam_(n+a) and the beam_(v+b).
 28. The apparatusof claim 20, wherein the at least one processor is configured todetermine the mapping by: determining that beam_(x) will be used as thefirst beam and that beam_(z) will be used as the second beam, beam_(x)and beam_(z) being uncorrelated.
 29. An apparatus for wirelesscommunication, the apparatus being a first device comprising: means fordetermining a mapping between a first beam associated with a first typeof channel and a second beam associated with a second type of channel,the first type of channel being different than the second type ofchannel; and means for receiving the first beam associated with thefirst type of channel and the second beam associated with the secondtype of channel, the first beam and the second beam being received froma second device.
 30. A computer-readable medium storing computerexecutable code, comprising code to: determine a mapping between a firstbeam associated with a first type of channel and a second beamassociated with a second type of channel, the first type of channelbeing different than the second type of channel; and receive the firstbeam associated with the first type of channel and the second beamassociated with the second type of channel, the first beam and thesecond beam being received from a second device.